Biomedical subjects

Y Nasu

Publications and source records attributed to Y Nasu.

At least 19 recordsLinked to original sources

PubMed2006

Induction of cell death in human papillomavirus 18-positive cervical cancer cells by E6 siRNA.

Human cervical cancer is caused by high-risk types of human papillomavirus (HPV) such as HPV16 and HPV18, which possess the E6 and E7 oncogenes, whose concurrent expression is a prerequisite for cancer development and maintaining malignant phenotypes. Silencing these oncogenes is considered to be applicable in molecular therapies of human cervical cancer. However, it remains to be determined whether E6, E7, or both should be silenced to obtain most efficient antitumor activity by an HPV small-interfering RNA (siRNA). Herein, we report two types of siRNAs targeting HPV18 E6, that exerted a negative growth effect on HPV18-positive cervical cancer cells (HeLa and SW756), in part, inducing cell death. One siRNA (Ex-18E6), designed to target both E6-E7 mRNA and its splicing variant, E6*I-E7 mRNA, efficiently knocked down both E6 and E7 expression. The other (Sp-18E6), designed to specifically target E6-E7 mRNA but not E6*I-E7 mRNA, suppressed E6 to a similar level as Ex-18E6; however, it less efficiently inhibited E7 as compared to Ex-18E6. Although both siRNAs induced cell death, Sp-18E6 siRNA induced more prominent cell death than Ex-18E6. Our results suggest that E6-specific suppression may induce more potent anticancer activity than simultaneous E6 and E7 suppression, and that E6-specific targeting is a promising strategy for siRNA-based therapy for HPV-positive cervical cancer.

Animals↗

PubMed2005

Adeno-associated virus-mediated human IL-10 gene transfer suppresses the development of experimental autoimmune orchitis.

Testicular germ cell-induced autoimmune orchitis is characterized by inflammatory cell infiltration followed by disturbance of spermatogenesis. Experimental autoimmune orchitis (EAO) is an animal model for human immunological male infertility; delayed-type hypersensitivity (DTH) response plays a key role in its induction. Interleukin-10 (IL-10) is a regulatory cytokine that is critical in preventing organ-specific autoimmune inflammation. To determine the effects on EAO of human IL-10 (hIL-10) gene transfer, C3H/He mice immunized by unilateral testicular injury were administered intramuscular (i.m.) injections of adeno-associated viral (AAV) vector-encoding hIL-10 on the day of immunization. Serum hIL-10 was detected beginning at 1 week postinjection, and peaked at 3 weeks. Histological examinations showed a significantly low incidence of orchitis and disturbance of spermatogenesis in AAV hIL-10-treated mice, and the DTH response to autologous testicular cells was significantly suppressed. Immunohistochemical analysis of IFN- and IL-2, T-cell-associated cytokines, in the spleen and testes revealed significantly fewer cytokine-expressing cells after treatment. We conclude that a single i.m. administration of AAV hIL-10 significantly suppresses EAO and hypospermatogenesis by regulating cell-mediated immunity in the testes.

Adenoviridae↗

PubMed2004

Analysis of retrograde ejaculation using color Doppler ultrasonography before and after transurethral collagen injection.

Transurethral bladder neck collagen injection therapy was performed in a patient with retrograde ejaculation. The phenomenon of retrograde ejaculation and its correction after the therapy were clearly demonstrated by color Doppler ultrasonography. To our knowledge this is the first report showing successful observation of retrograde ejaculation using color Doppler ultrasonography.

Adult↗

PubMed2002

Gene therapy for prostate cancer: toxicological profile of four HSV-tk transducing adenoviral vectors regulated by different promoters.

Adenoviral vector delivery of the Herpes simplex virus thymidine kinase (HSV-tk) gene in combination with the prodrug ganciclovir (GCV) has been tested in phase I clinical trials for prostate cancer and found to exhibit a satisfactory toxicity profile. We have developed additional adenoviral vectors with differing promoters to optimize the expression profile and in the present study evaluate the potential systemic toxicity of these vectors. Four recombinant adenoviral vectors that express the HSV-tk gene were generated using three different promoters: CMV (leftward orientation); RSV (both rightward and leftward orientation); and the mouse caveolin-1 (cav-1) promoter (leftward orientation). Efficacy was determined in vitro by cytotoxicity assays in a mouse prostate cancer cell line, RM-9, and in vivo by treating orthotopic tumors. Potential toxicity was evaluated from liver histology and apoptotic cell counts and enzyme levels in the serum following intravenous adenoviral vector injection. Although there were differences in HSV-tk expression at the protein level among the four vectors there were no significant differences in in-vitro cytotoxicity studies with GCV or in vivo in tumor growth suppression of an orthotopic mouse prostate cancer model in GCV treated mice. Intravenous delivery of high doses of all adenoviral vectors lead to abnormalities in liver function as measured by specific serum markers and histological evaluation of liver tissue and increased levels of apoptosis in the liver. These abnormalities were most prevalent with the vector containing the CMV promoter and the rightward oriented RSV promoter. They were least prevalent in the vector regulated by the cav-1 promoter. Upregulation of specific chemokines, MIP-2 and MIP-1beta was correlated with apoptotic counts. Our results demonstrate that comprehensive toxicological analysis of adenoviral vectors provides internally consistent information that can differentiate vectors with comparable efficacy based on toxicity. In these studies vectors with the cav-1 promoter-driven and leftward RSV-driven HSV-tk gene demonstrated minimal toxicities with cytotoxic effectiveness comparable to more toxic vectors. Our studies further suggest that promoter selection can influence the toxic effects of an adenoviral gene therapy vector.

Adenocarcinoma↗

PubMed2002

Validation of transrectal ultrasonographic volumetry for orthotopic prostate tumours in mice.

Orthotopic human prostate tumour models in athymic nude mice are regarded as being most suitable for fundamental and pre-clinical research on prostate cancer. The anatomic localization of the tumour in the pelvis, however, provides little possibility for monitoring tumour growth or regression. To assess time-related changes in orthotopic tumour volume, we applied transrectal ultrasonography (TRUS) to the murine prostate. This technique has the advantages of allowing accurate monitoring of tumours during therapeutic manipulations and a reduction of animal use due to a reduction of sacrificing endpoints. To validate the TRUS method, the mouse prostate reconstitution model, RM-9, and the prostate-specific antigen (PSA) producing human prostate cancer xenograft PC-346 were used. Volumetric calliper measurements were performed with a 30 MHz ultrasound probe designed for intra-arterial use in humans. Tumour weight, determined at various time-points, was found to be closely related to actual tumour weight (R = 0.99) and, in the PC-346 model, to the level of PSA in the plasma. Furthermore, the interobserver variation for TRUS was low for tumours above 50 mg. Thus, TRUS for murine prostate tumours proves to be an accurate, reproducible and sensitive method.

Animals↗

PubMed2001

Caveolin-1 mediates testosterone-stimulated survival/clonal growth and promotes metastatic activities in prostate cancer cells.

Previously, we demonstrated that up-regulation of caveolin-1 (cav-1) was associated with prostate cancer metastasis, biochemical recurrence after radical prostatectomy, and androgen insensitivity. The objective of this study was to characterize the regulation of cav-1 by testosterone (T) and to test the effects of cav-1 on prostate cancer cell survival/clonal growth and metastatic activities. Our results demonstrated that T up-regulated cav-1 protein levels in part through transcriptional regulation and significantly enhanced survival of prostate cancer cell lines ABAC3 and LNCaP after serum starvation (>40% and >60% increased viability, respectively) and in an extended clonogenic assay (approximately 4-fold and 6-fold increase in colonies, respectively). Importantly, antisense cav-1 inhibited the survival effects of T in these assay systems. Modest but not high levels of adenoviral vector-mediated cav-1 expression alone also significantly increased viability (>40%) and clonal growth (10-fold increase in colonies) after serum starvation. Analysis of spontaneous metastasis in stably transfected antisense cav-1 mouse prostate cancer cell clones demonstrated reduction of spontaneous lymph node metastasis incidence (13%), spontaneous lymph node metastasis volume (46%), and experimental lung metastasis incidence (40%) compared with vector control cell clones. Surgical castration further reduced spontaneous lymph node metastasis incidence and volume (18% and 28%, respectively) in antisense cancer cell clones, but not in vector control clones. Our studies demonstrate that cav-1 is a downstream effector of T-mediated prostate cancer cell survival/clonal growth and that modest levels of cav-1 can independently promote prostate cancer cell survival/clonal growth and metastatic activities.

Animals↗

PubMed2001

Transrectal ultrasound for monitoring murine orthotopic prostate tumor.

BACKGROUND: The mouse orthotopic prostate tumor model has been recognized as an ideal preclinical animal model simulating the anatomical and biological milieu of the prostate. In comparison with the subcutaneous tumor model, the only disadvantage of this model is the difficulty of chronological tumor growth monitoring. We have applied recent endoluminal ultrasound technology, transrectal ultrasonography (TRUS), to the monitoring of mouse orthotopic prostate tumors. METHODS: A 6 Fr. 20 MHz catheter-based radial scan probe was used and TRUS was performed without any prior preparation including anesthesia. Orthotopic tumors were initiated by inoculation of 5000 RM-9 cells into the dorsal prostate of 12-week-old C57BL/6 male mice. The tumor growth was monitored by TRUS from day 3 to day 21. In addition, TRUS was performed to detect tumor growth suppression after intraperitoneal administration of cis-diamminedichloroplatinum (CDDP). RESULTS: By ultrasound, tumors became detectable 7 days after tumor cell inoculation. TRUS images were clear and parallel to actual tumor growth. The tumor volume (X) calculated by TRUS correlated significantly with the actual tumor weight (Y) measured at autopsy; Y = 101.653 + 1.174X (R = 0.930, P < 0.001). Similarly, tumor growth suppression induced by CDDP was clearly detected by TRUS with reasonable accuracy. CONCLUSIONS: A high resolution TRUS allows simple and reliable monitoring of in situ tumor growth and growth suppression, making the mouse orthotopic prostate tumor model more efficient.

Animals↗

PubMed2001

Distribution of cellular isoform of prion protein in T lymphocytes and bone marrow, analyzed by wild-type and prion protein gene-deficient mice.

In this study, the authors investigated normal cellular prion protein (PrP(C)) expression on murine immune systems using prion protein gene-deficient mouse as negative control. Immunocytes expressing PrP(C) in adult and fetal mice were detected by flow cytometry with the monoclonal antibody against PrP(C), 6H4. Cells from thymus and bone marrow reacted positively with 6H4, while spleen cells, peritoneal cells, peripheral blood leukocytes, and intestinal intraepithelial lymphocytes were nonreactive. In thymus, PrP(C) was observed in CD4(-)CD8(-) double-negative thymocytes. PrP(C+) cells of double-negative thymocytes belonged to the CD3(-) subset, but not to the CD3(+) subset. Triple-negative PrP(C+) thymocytes expressed CD44 or CD25 antigens. Furthermore, PrP(C) was observed in c-kit(+) bone marrow cells. In fetuses, PrP(C+) cells were observed in the liver and thymus at day 16.0 and 15.0 of gestation, respectively. These results demonstrated that PrP(C) is expressed on immature immunocytes.

Animals↗

PubMed2001

Combination gene therapy with adenoviral vector-mediated HSV-tk+GCV and IL-12 in an orthotopic mouse model for prostate cancer.

We previously demonstrated significant therapeutic activities associated with adenoviral vector-mediated Herpes Simplex Virus/thymidine kinase (AdHSV-tk) with ganciclovir (GCV) in situ gene therapy in the RM-1 orthotopic mouse prostate cancer model and interleukin-12 (AdmIL-12) in situ gene therapy in the RM-9 orthotopic mouse prostate model for prostate cancer. In both protocols, local cytotoxicity and activities against pre-established lung metastases were demonstrated. To test whether combined AdHSV-tk+GCV+IL-12 gene therapy would lead to enhanced therapeutic effects when compared to either treatment alone, we used RM-9 mouse prostate cancer cells in both orthotopic and pre-established lung metastases models of prostate cancer. Combined treatment with a single injection of optimal doses of AdHSV-tk+GCV or AdmIL-12 led to significantly increased suppression of orthotopic tumor growth. IL-12 gene therapy alone was more effective than AdHSV-tk+GCV in suppressing spontaneous lymph node metastases and pre-established lung metastases but combination gene therapy did not result in additional anti-metastatic activities. Combination gene therapy also did not achieve significantly better animal survival compared to AdHSV-tk+GCV or AdmIL-12 alone. Analysis of localized antitumor activities demonstrated that AdHSV-tk+GCV therapy induced higher levels of necrosis compared to AdmIL-12 or combination therapy. However, both treatments alone and combination therapy produced similar increases in apoptotic index. To address the possible mechanisms of locally co-operative cytotoxic activities, we analyzed the systemic natural killer (NK) response and the numbers of tumor-infiltrating immune cells using quantitative immunohistochemical analysis. AdHSV-tk+GCV therapy alone led to detectable increases in iNOS-positive cells, CD4+and CD8+T-cells and moderately increased numbers of F4/80 (macrophage selective)-positive cells within treated tumors. In contrast, AdmIL-12 elicited a highly robust pattern of tumor infiltration for all four of these immune cells that was in general mimicked by combination therapy. Further analysis of the accumulation of transforming growth factor-beta1 (TGF-beta1) immunohistochemical staining demonstrated that AdHSV-tk+GCV treatment, but not AdmIL-12 treatment, produced cancer cell-associated increases in this cytokine relative to control Ad-beta-gal injections. Interestingly, local injection with AdHSV-tk+GCV induced significant splenocyte-derived NK cell cytolytic activities with maximal response 7 days following treatment, whereas AdmIL-12 injection produced significantly higher NK activity with maximal response 2 days following injection. The combined treatment produced a higher systemic NK response over the 14-day treatment period. Depletion of NK cells in vivo demonstrated that this immunocyte subpopulation was responsible for early locally cytotoxic activities induced by AdHSV-tk+GCV but not AdmIL-12 and that NK activities were largely responsible for activities against pre-established metastases generated by both gene therapy protocols. Prostate Cancer and Prostatic Diseases (2001) 4, 44-55

Journal Article↗

PubMed2001

Treatment of androgen-independent prostate cancer with dexamethasone: a prospective study in stage D2 patients.

PURPOSE: In order to evaluate the efficacy of dexamethasone in the treatment of Japanese men with androgen-independent prostate cancer, a prospective study was conducted using prostate-specific antigen (PSA) as a primary end-point. METHODS: Nineteen Japanese men with stage D2 androgen-independent prostate cancer were registered and treatment was started. After ruling out anti-androgen withdrawal syndrome, they were treated with dexamethasone (1.5 mg daily). Patients were monitored for PSA, symptoms, radiologic response, survival rate, time to disease progression, time to treatment failure and complications. RESULTS: Prostate-specific antigen levels decreased in nine patients (50.0%); five (27.8%) showed a 50% or greater decrease and two (11.1%) showed an 80% or greater decrease. For the nine patients, the mean duration of PSA response was 7.3 months and the median duration was 2.1 months (range, 1.2-27.5+). Bone pain, which was noted in 13 patients at study entry, improved in seven patients (53.8%). Of nine patients who had serial radiographic examinations with bone scan, three (33%) showed partial response, two (22%) were stable and four (44%) showed disease progression. Treatment was well tolerated, except for one patient who suffered a severe pulmonary infection. CONCLUSION: Dexamethasone decreased PSA levels and produced subjective symptomatic improvement in the patients with stage D2 androgen-independent prostate cancer.

Aged↗

PubMed2001

Orthotopic neobladder reconstruction in elderly bladder cancer patients.

BACKGROUND: We compared the clinical results of orthotopic neobladder reconstruction in elderly patients and those in younger patients retrospectively in order to verify whether age is a critical factor in selecting a method of urinary diversion. METHODS: Following radical cystectomy for bladder cancer, 12 patients aged 75 or older and 17 patients under 75 who underwent orthotopic neobladder reconstruction between January 1992 and May 1999 were investigated in this study. The authors TS and BS were among the surgeons who performed operations for all cases. Of the 12 elderly patients, orthotopic neobladders were constructed according to Hautmann's method in nine cases, Studer's method in one case and Reddy's method in two cases. Of the 17 younger patients, these methods were employed in 12, one and four cases, respectively. Operative procedure, early and late complications, prognosis, continence and voiding pattern were investigated in these patients. RESULTS: The follow-up periods for elderly and younger groups ranged from 21.3 to 82.7 months and from 8.8 to 94.2 months, respectively. No difference in operation time, amount of bleeding or postoperative length of hospitalization was observed between elderly and younger patients. The rates of early complications in elderly and younger patients were 41.7% and 35.3%, respectively. Late complication rates were 33.3% and 47.1%, respectively. The difference in these complication rates was not statistically significant. One of the elderly and two of the younger patients had local recurrence and metastasis postoperatively. Those three patients had died of their bladder cancer. No statistically significant difference between groups was recognized in either cause-specific survival or overall survival, nor was there such a difference in relation to micturition/continence. CONCLUSION: Based on these results, we believe that because age is not a critical factor in the selection of urinary diversion method, neobladder reconstruction following cystectomy for bladder cancer is indicated in elderly patients. As stoma management is difficult for the patients, we consider orthotopic neobladder reconstruction to be the method of choice if the patients' general physical condition allows.

Age Factors↗

PubMed2001

Retroperitoneoscopic pyelotomy combined with the transposition of crossing vessels for ureteropelvic junction obstruction.

PURPOSE: We developed a new approach of retroperitoneoscopic pyelotomy combined with the transposition of crossing vessels for ureteropelvic junction obstruction as an alternative to conventional antegrade or retrograde endopyelotomy. MATERIALS AND METHODS: From February 1997 to August 1999 we treated 5 cases of ureteropelvic junction obstruction due to crossing vessels that were diagnosed by helical computerized tomography. Ureterovascular hydronephrosis characterized by a malrotated renal pelvis with anterior crossing vessels was observed in 4 cases and ureteropelvic junction obstruction with a posterior crossing artery was present in 1. After endoureterotomy stent insertion under cystoscopic guidance we performed retroperitoneoscopic endopyelotomy with the kidney in standard position. Crossing vessels were transposed to a higher position to remove obstruction and fixed with peripelvic tissue via retroperitoneoscopy. In all cases a longitudinal incision approximately 1.5 cm. long was made with a potassium titanyl phosphate laser. RESULTS: Convalescence was uneventful in all patients and the endoureterotomy stent was removed 4 to 8 weeks after surgery. Postoperatively helical computerized tomography showed the successful transposition of crossing vessels and significant hydronephrosis resolution in all cases. All patients were asymptomatic during followup of 17 to 28 months. CONCLUSIONS: Despite our small number of patients our results are sufficient to conclude that retroperitoneoscopic pyelotomy combined with the transposition of crossing vessels is a simple and reliable method for treating ureterovascular hydronephrosis and associated conditions.

Adult↗

PubMed2001

Comparative analysis of the prion protein open reading frame nucleotide sequences of two wild ruminants, the moufflon and golden takin.

The prion protein (PrP) nucleotide sequences of two ruminants were determined in order to elucidate the differences in susceptibility to spongiform encephalopathy agents in each species. The nucleotide sequences of PrP coding regions of the moufflon and the golden takin encompassed 771 bp in length. The PrP gene sequences of the golden takin were closely related to those of sheep with one amino acid difference. The PrP gene sequence of the moufflon was identical to that of sheep. The similarities between the PrP genes of these two animals and sheep imply that the species barriers between these animals are small or non-existent. These PrP genes could be used to establish transgenic mice with higher susceptibility to prion-related diseases.

Amino Acid Sequence↗

PubMed2001

Optimal starting time for flutamide to prevent disease flare in prostate cancer patients treated with a gonadotropin-releasing hormone agonist.

OBJECTIVE: Flare-up phenomena, such as an increase in prostate-specific antigen (PSA) and/or deterioration of symptoms, are observed in some patients undergoing gonadotropin-releasing hormone (GnRH) agonist therapy. This study was carried out to determine the optimal time for starting the administration of flutamide to prevent flare-up phenomena. PATIENTS AND METHODS: Twenty-six patients with prostate cancer and elevated serum levels of PSA were randomly assigned to 5 groups. Group A patients (n = 6) were treated with a subcutaneous injection of 3.75 mg leuprorelin acetate depot alone. Group B, C, D and E patients (5 patients in each group) were treated with 375 mg/day of orally administered flutamide combined with leuprorelin. Flutamide was initiated on the day of leuprorelin injection in group B, and at 1, 2 and 4 weeks before leuprorelin injection in groups C, D and E, respectively. Serum PSA and testosterone levels were measured in each patient. RESULTS: Pretreatment with flutamide increased the serum testosterone level, but the testosterone surge after leuprorelin administration was almost the same in all 5 treatment groups. In patients who had been treated with flutamide in combination with leuprorelin, the mean PSA level did not exceed the pretreatment levels after leuprorelin administration. The rate of decrease in PSA in the group receiving simultaneous administration of flutamide with leuprorelin showed a decline comparable to that during the period before leuprorelin administration in the flutamide pretreatment groups. CONCLUSION: Simultaneous administration of flutamide with a GnRH agonist is sufficient to prevent flare-up phenomena.

Adenocarcinoma↗

PubMed2001

Prostate cancer gene therapy-what have we learned and where are we going?

With recent advances in genetic engineering, tumor biology, and immunology, gene therapy has been recognized as a promising new treatment option for various cancers, including prostate cancer. Several clinical trials of prostate cancer gene therapy, using therapeutic genes which include suicide genes, immunomodulatory genes, tumor suppressor genes, and anti-oncogenes, are under way and preliminary reports have emerged. Although gene therapy for prostate cancer is still at an early stage and requires additional technological breakthroughs, new insights obtained from recent clinical trials indicate a promising potential for prostate cancer gene therapy. In this report, general concepts, current progress, and future prospects in prostate cancer gene therapy are summarized.

Journal Article↗

PubMed2000

Reliability of color Doppler ultrasound urodynamics in the evaluation of bladder outlet obstruction.

OBJECTIVES: To analyze the intrarater and interrater reliability of a newly developed noninvasive urodynamic technique based on color Doppler ultrasound for the evaluation of bladder outlet obstruction. We previously demonstrated the feasibility of this new technique. METHODS: Color Doppler ultrasound urodynamic evaluations were performed on 31 men with and without bladder outlet obstruction. An ultrasound image-directed Doppler system with a 3.75-MHz probe operated by a remote control robotic manipulator was used to obtain color scale data using the transperineal approach in men during voiding. We measured the flow velocities in the distal prostatic (V1) and membranous urethra (V2) and used them to obtain the velocity ratio (VR = V1/V2). Combining this information with simultaneous uroflowmetry, the functional cross-sectional area of the distal prostatic urethra (A1) was calculated. These parameters were independently reinterpreted by an inexperienced investigator using the color image data stored in a personal computer. The intrarater and interrater reliability for VR were assessed using a classification based on cutoff values previously shown to indicate the presence or absence of obstruction. RESULTS: The retest correlation using Spearman's rho for VR in terms of intrarater and interrater reliability was 0.95 and 0.57, respectively; that for A1 was 0.97 and 0.64, respectively. Using a VR of less than 1.1 (to indicate the absence of obstruction) and a VR greater than 1.6 (to indicate the presence of obstruction) for classification, intrarater and interrater agreement occurred in 93.6% to 96.8% and 77.4% to 83. 9% of cases, respectively. CONCLUSIONS: The color Doppler ultrasound urodynamic technique for noninvasive evaluation of bladder outlet obstruction can be performed with reasonable reliability.

Adult↗

PubMed2000

Noninvasive urodynamic evaluation of bladder outlet obstruction using Doppler ultrasonography.

OBJECTIVES: Previously we had developed a new method of noninvasive urodynamics using color Doppler ultrasound. Using this technique, we attempted to identify parameters that would diagnose bladder outlet obstruction (BOO). METHODS: Twenty-two men who underwent pressure-flow urodynamic studies were included. Color scale transperineal ultrasound and uroflowmetry data were analyzed by custom-made software. The maximum flow velocities in the entire prostatic urethra (V(0)), in the distal prostatic urethra just proximal to the external urethral sphincter (V(1)), and in the membranous urethra (V(2)) were obtained. Corresponding functional cross-sectional areas of the urethra at these three sites (A(0), A(1), and A(2)) were calculated as Qmax/V. The velocity ratio (VR), which was equal to V(1)/V(2), was also calculated as a parameter. All these parameters obtained by the velocity-flow urodynamics were compared with the Abrams-Griffiths number (AG). RESULTS: From the x-y plots obtained, VR correlated best with AG, with Spearman's rho of 0. 728. A(0) and A(1) had rho values of -0.461 and -0.708 against AG, respectively. All men with VR exceeding 1.6 had obstruction, whereas those with VR less than 1.1 did not. CONCLUSIONS: The VR was found to be the best parameter for diagnosing BOO. When prostatic urethral obstruction was present, the velocity in the prostatic urethra would be high but the velocity slows down to 62.5% or greater immediately below the sphincter. We believe that noninvasive pressure-flow-like urodynamic evaluation based on Doppler ultrasound has clear potential for diagnosing BOO.

Humans↗

PubMed2000

Enhanced expression of cellular prion protein gene by insulin or nerve growth factor in immortalized mouse neuronal precursor cell lines.

In order to understand the fundamental and putative roles of PrP(c) in the central nervous system, neuronal cell lines were established. Cells were immortalized by recombinant retrovirus vector-mediated transduction of SV40 T-antigen gene. Among these, two cell lines were selected based on their RT-PCR expressions of neuron-specific neurofilament (NF-H, NF-M) and cell morphology. These cell lines showed the properties of neuronal progenitor cells in antigenicity, morphology and responses to differentiating agents. Expression of PrP(c) was detected by immunocytochemical analysis. These cell lines responded to differentiating agents such as dibutyl cyclic AMP (dcAMP) and phorbol 12-myristate 13-acetate (PMA) before developing into neuronal-like cells. Neurite extensions were observed 20 min after incubation with the differentiating agents. Treatment with nerve growth factor (NGF) and insulin induced cell differentiation and enhanced expression of PrP gene (Prnp) mRNA and protein. The latter phenomenon was not inhibited by wortmannin, which is a specific inhibitor of phosphatidylinositol 3-kinase. These results suggest that PrP(c) plays an important role in the differentiation-mediated classic signaling pathway of neuronal cell.

Androstadienes↗